The manufacture of note producing musical instruments began as a search for the mechanical equivalent of the human voice. This in fact remained the standard through the Middle Ages and into the Renaissance and the early modern period.
Stringed instruments have been known since ancient times. These included such instruments as the lute, a guitar-like instrument with a sound box and fingerboard. A New Kingdom (ancient Egypt, 1380 BC) bronze in the collection of the Metropolitan Museum of Art depicts a dancing Nubian raised on his toes with one knee cocked, left hand high working a fingerboard and right hand plucking the strings in a pose which might be illustrative of a modern rock musician.
But the lute has a much more ancient history, perhaps originating with West Semitic nomadic people who brought the instrument to Mesopotamia, where the archaeological record includes representations dating back to the Akkadian period (2350 to 2170 B.C.), being introduced to the Egyptians, perhaps at the end of the Middle Kingdom Hyksos dynasties (XV to XVII dynasty, 1730 to 1580 B.C.).
In more recent times, stringed lute-like musical instruments continue to be among the most popular instruments. Folk artists throughout the United States have used the guitar, sometimes one of the homemade varieties, in a wide range of musical genres including blues, bluegrass, and so forth.
In contrast to percussive instrumentation, the need for amplification of the relatively weak sounds of strings, reeds, and vibrating human lips presented challenges to early musical instrument manufacturers. These challenges were met primarily by resonant systems that mechanically concentrate, and output musical sound. There is a demanding standard in the stability of the instrument if high-quality sound is to be produced.
Moreover, over the years, artists playing acoustic stringed instruments have introduced a wide variety of playing techniques into the music surrounding these instruments. While, perhaps, the ancients only plucked the strings of the lute to achieve a musical tone which gradually decayed, later artists used the bow to produce notes of relatively constant and somewhat controllable amplitude. Modern artists employ a variety of techniques in their performances. Acoustic blues performers may rap their instruments with fingertips, palms or knuckles. Certain violin compositions, typically played by having a horsehair bundle slide across the strings, also call for the strings to be plucked. This results in yet greater demands being put on the mechanical stability of the instrument.
Given the popularity of stringed musical instruments, especially the guitar, people often take them along when traveling. However, they are bulky and poorly suited to convenient transport. They are unlikely to fit into airlines stowaway spaces or under airline seats. In response to this need, guitars with folding necks have been proposed. See for example my earlier U.S. Design Pat. No. 516,114, and my earlier pending U.S. patent application Ser. No. 11/640,095, filed Dec. 15, 2006. While this instrument is effective, it is difficult to make requiring significant handwork and fine tuning.
In order for a hinged neck traveling guitar to be used, one must employ a latch to hold the neck in the playing position after the neck has been moved from the travel or storage position to the playing position by rotation of the neck about the hinge. This latch should be easy to use and at the same time positively lock the neck in the proper position, or the acoustics of the guitar will be degraded.